``Welcome to my computer zoo,'' writes Pickover ( Computers and the Imagination ), a salutation that at some point during his tour of more than 200 ``mind mazes'' begins to seem increasingly worthy of Lewis Carroll's Mad Queen or Mary Shelley's Dr. Frankenstein. Fans of the Scientific American ``Puzzling'' column will recognize this book's genre, though it gradually, almost magically changes into something more challenging and weird. Pickover clearly enjoys the extra dimensions that computing affords recreational math puzzlers; he seems to have saved up a lifetime's worth of math teasers for this explosion-in-the-algorithmsp ok -factory collection. The length, complexity and level of difficulty varies wildly within the seven categories (from ``Pattern'' to ``Weird Numbers''): some clearly require considerable knowledge and a PC to match, but just as many are more easily accessible and solvable. Enhanced by quirky design, this volume is the perfect tool with which to instill instant humility in any self-proclaimed math or computer whiz. ( Nov. )